Showing papers in "Theoretical Computer Science in 2005"

TL;DR: A survey on theoretical results on ant colony optimization, which highlights some open questions with a certain interest of being solved in the near future and discusses relations between ant colonies optimization algorithms and other approximate methods for optimization.

TL;DR: This paper gives an algebraic specification that selects, among all solutions to the data exchange problem, a special class of solutions that is called universal and shows that a universal solution has no more and no less data than required for data exchange and that it represents the entire space of possible solutions.

TL;DR: This work surveys the problem of comparing labeled trees based on simple local operations of deleting, inserting, and relabeling nodes and presents one or more of the central algorithms for solving the problem.

TL;DR: The main goal is to provide a tutorial of CA theory to researchers in other branches of natural computing, to give a compact collection of known results with references to their proofs, and to suggest some open problems.

TL;DR: This paper presents a protocol that allows anonymous oblivious robots with limited visibility to gather in the same location in finite time, provided they have orientation (i.e., agreement on a coordinate system), indicating that, with respect to gathering, orientation is at least as powerful as instantaneous movements.

TL;DR: The history of process algebra as an area of research in concurrency theory, the theory of parallel and distributed systems in computer science is discussed in this paper, where the author gives his personal views on these matters.

TL;DR: In this article, the authors present a non-deterministic model of computation based on reversing edge directions in weighted directed graphs with minimum in-flow constraints on vertices, and show that deciding whether a simple graph model can be manipulated in order to reverse the direction of a particular edge is PSPACE-complete by a reduction from Quantified Boolean Formulas.

TL;DR: A stronger lower bound and an upper bound matching the lower bound are provided that determining the winner in Kemeny's system is complete for P||NP, the class of sets solvable via parallel access to NP.

TL;DR: This paper construct several classes of authentication codes using several types of error correcting codes and finds that some of the authentication codes constructed here are asymptotically optimal, and some are optimal.

TL;DR: It is shown that morphisms between containers can be full and faithfully interpreted as polymorphic functions (i.e. natural transformations) and that, in the presence of W-types, all strictly positive types give rise to containers.

TL;DR: In this work, an extension of the k-center facility location problem, where centers are required to service a minimum of clients is studied, and three variants of this problem are shown to be N P-hard.

TL;DR: In this article, a monoid structure on the set of binary search trees is introduced, by a process very similar to the construction of the plactic monoid, the Robinson-Schensted insertion being replaced by the binary search tree insertion.

TL;DR: This work considers tissue-like P systems with states associated with the links between cells, controlling the passage of objects across the links, and investigates the computing power of such devices for the case of using--in a sequential manner--antiport rules of small weights.

TL;DR: Structural properties of each of the main sublanguages of navigational XPath (W3c Recommendation) commonly used in practice are studied, providing sound and complete axiom systems and normal forms for several of these fragments.

TL;DR: Inspired by the categorical framework of Joyal, Nielsen and Winskel, novel notions of bisimulation equivalence for dynamical systems as well as control systems are developed and it is proved that these notions can be captured by the abstract notion of Bisimulation.

TL;DR: The negative of the new randomness test is shown to be a generalization of complexity in continuous spaces and it is shown that the addition theorem survives.

TL;DR: From the combination of knowledge and actions, someone can improve their skill and ability and this graph colorings tells you that any book will give certain knowledge to take all benefits.

TL;DR: This paper proposes new constructions for DNA codes satisfying either a reverse-complement constraint, a GC-content constraint, or both, that are derived from additive and linear codes over four-letter alphabets.

TL;DR: It is shown that, for a finitary set functor, this construction always yields a final coalgebra in ω2 = ω + ω steps.

TL;DR: This paper investigates theoretically the (1, λ)-SA-ES on the well known sphere function and proves sufficient conditions on the parameters of the algorithm ensuring the convergence of 1/n ln(||Xn||), where Xn is the parent at generation n.

TL;DR: A representation theorem for Boolean contact algebras is proved which implies that the axioms for the region connection calculus (RCC) are complete for the class of subalgebra of the algeBRas of regular closed sets of weakly regular connected T1 spaces.

TL;DR: The present paper aims at studying the power and limitation of Alb's, and generalizes the three known Alb's and gives a new Alb style lower bound method, which may be easier to use for some problems.

TL;DR: A framework consisting of combining automated test case generation based on systematically exploring the input domain of the program with runtime verification, where execution traces are monitored and verified against properties expressed in temporal logic is reported.

TL;DR: The dichotomy theorem proved by Hell and Nesetřil is shown to be correct and the criterion distinguishing the tractable cases of the H-Coloring problem agrees with that conjectured in A.A. Krokhin's Constraint satisfaction problems and finite algebras.

TL;DR: In this article, a process algebra obtained by extending a combination of the process algebra with continuous relative timing from Baeten and Middelburg (Process Algebra with Timing, Springer, Berlin, 2002, Chapter 4) and the process algebra with propositional signals from Bergstra and Bergstra (Theoret. Comput. Sci. 177 (1977) 381-405).

TL;DR: This work shows how high-level functional programs can be mapped compositionally into a simple kind of automata which are immediately seen to be reversible.

TL;DR: A mechanization of the quantitative logic for pGCL using the HOL theorem prover is presented, including a proof that all p GCL commands, satisfy the new condition sublinearity, the quantitative generalization of conjunctivity for standard GCL.

TL;DR: The maximum agreement phylogenetic subnetwork problem (MASN) is introduced and it is proved that the problem is NP-hard even if restricted to three phylogenetic networks and an O(n2)-time algorithm is given for the special case of two level-1 phylogenetics networks.

TL;DR: A structured mathematical definition of the semantics of C# programs is proposed to provide a platform-independent interpreter view of the language for the C# programmer and to provide for implementors the possibility to check their basic design decisions against an accurate high-level model.

TL;DR: This work provides an algorithm for the restricted case of separable 2SAT formulae, with fast running times for well-studied input classes, and develops new measures of formula complexity, allowing us to conveniently analyze the effects of certain factors with a large impact on the total running time.